hw/vfio/platform.c

   1 /*
   2  * vfio based device assignment support - platform devices
   3  *
   4  * Copyright Linaro Limited, 2014
   5  *
   6  * Authors:
   7  *  Kim Phillips <kim.phillips@linaro.org>
   8  *  Eric Auger <eric.auger@linaro.org>
   9  *
  10  * This work is licensed under the terms of the GNU GPL, version 2.  See
  11  * the COPYING file in the top-level directory.
  12  *
  13  * Based on vfio based PCI device assignment support:
  14  *  Copyright Red Hat, Inc. 2012
  15  */
  16
  17 #include "qemu/osdep.h"
  18 #include "qapi/error.h"
  19 #include <sys/ioctl.h>
  20 #include <linux/vfio.h>
  21
  22 #include "hw/vfio/vfio-platform.h"
  23 #include "migration/vmstate.h"
  24 #include "qemu/error-report.h"
  25 #include "qemu/lockable.h"
  26 #include "qemu/main-loop.h"
  27 #include "qemu/module.h"
  28 #include "qemu/range.h"
  29 #include "exec/memory.h"
  30 #include "exec/address-spaces.h"
  31 #include "qemu/queue.h"
  32 #include "hw/sysbus.h"
  33 #include "trace.h"
  34 #include "hw/irq.h"
  35 #include "hw/platform-bus.h"
  36 #include "hw/qdev-properties.h"
  37 #include "sysemu/kvm.h"
  38
  39 /*
  40  * Functions used whatever the injection method
  41  */
  42
  43 static inline bool vfio_irq_is_automasked(VFIOINTp *intp)
  44 {
  45     return intp->flags & VFIO_IRQ_INFO_AUTOMASKED;
  46 }
  47
  48 /**
  49  * vfio_init_intp - allocate, initialize the IRQ struct pointer
  50  * and add it into the list of IRQs
  51  * @vbasedev: the VFIO device handle
  52  * @info: irq info struct retrieved from VFIO driver
  53  * @errp: error object
  54  */
  55 static VFIOINTp *vfio_init_intp(VFIODevice *vbasedev,
  56                                 struct vfio_irq_info info, Error **errp)
  57 {
  58     int ret;
  59     VFIOPlatformDevice *vdev =
  60         container_of(vbasedev, VFIOPlatformDevice, vbasedev);
  61     SysBusDevice *sbdev = SYS_BUS_DEVICE(vdev);
  62     VFIOINTp *intp;
  63
  64     intp = g_malloc0(sizeof(*intp));
  65     intp->vdev = vdev;
  66     intp->pin = info.index;
  67     intp->flags = info.flags;
  68     intp->state = VFIO_IRQ_INACTIVE;
  69     intp->kvm_accel = false;
  70
  71     sysbus_init_irq(sbdev, &intp->qemuirq);
  72
  73     /* Get an eventfd for trigger */
  74     intp->interrupt = g_malloc0(sizeof(EventNotifier));
  75     ret = event_notifier_init(intp->interrupt, 0);
  76     if (ret) {
  77         g_free(intp->interrupt);
  78         g_free(intp);
  79         error_setg_errno(errp, -ret,
  80                          "failed to initialize trigger eventfd notifier");
  81         return NULL;
  82     }
  83     if (vfio_irq_is_automasked(intp)) {
  84         /* Get an eventfd for resample/unmask */
  85         intp->unmask = g_malloc0(sizeof(EventNotifier));
  86         ret = event_notifier_init(intp->unmask, 0);
  87         if (ret) {
  88             g_free(intp->interrupt);
  89             g_free(intp->unmask);
  90             g_free(intp);
  91             error_setg_errno(errp, -ret,
  92                              "failed to initialize resample eventfd notifier");
  93             return NULL;
  94         }
  95     }
  96
  97     QLIST_INSERT_HEAD(&vdev->intp_list, intp, next);
  98     return intp;
  99 }
 100
 101 /**
 102  * vfio_set_trigger_eventfd - set VFIO eventfd handling
 103  *
 104  * @intp: IRQ struct handle
 105  * @handler: handler to be called on eventfd signaling
 106  *
 107  * Setup VFIO signaling and attach an optional user-side handler
 108  * to the eventfd
 109  */
 110 static int vfio_set_trigger_eventfd(VFIOINTp *intp,
 111                                     eventfd_user_side_handler_t handler)
 112 {
 113     VFIODevice *vbasedev = &intp->vdev->vbasedev;
 114     int32_t fd = event_notifier_get_fd(intp->interrupt);
 115     Error *err = NULL;
 116     int ret;
 117
 118     qemu_set_fd_handler(fd, (IOHandler *)handler, NULL, intp);
 119
 120     ret = vfio_set_irq_signaling(vbasedev, intp->pin, 0,
 121                                  VFIO_IRQ_SET_ACTION_TRIGGER, fd, &err);
 122     if (ret) {
 123         error_reportf_err(err, VFIO_MSG_PREFIX, vbasedev->name);
 124         qemu_set_fd_handler(fd, NULL, NULL, NULL);
 125     }
 126
 127     return ret;
 128 }
 129
 130 /*
 131  * Functions only used when eventfds are handled on user-side
 132  * ie. without irqfd
 133  */
 134
 135 /**
 136  * vfio_mmap_set_enabled - enable/disable the fast path mode
 137  * @vdev: the VFIO platform device
 138  * @enabled: the target mmap state
 139  *
 140  * enabled = true ~ fast path = MMIO region is mmaped (no KVM TRAP);
 141  * enabled = false ~ slow path = MMIO region is trapped and region callbacks
 142  * are called; slow path enables to trap the device IRQ status register reset
 143 */
 144
 145 static void vfio_mmap_set_enabled(VFIOPlatformDevice *vdev, bool enabled)
 146 {
 147     int i;
 148
 149     for (i = 0; i < vdev->vbasedev.num_regions; i++) {
 150         vfio_region_mmaps_set_enabled(vdev->regions[i], enabled);
 151     }
 152 }
 153
 154 /**
 155  * vfio_intp_mmap_enable - timer function, restores the fast path
 156  * if there is no more active IRQ
 157  * @opaque: actually points to the VFIO platform device
 158  *
 159  * Called on mmap timer timout, this function checks whether the
 160  * IRQ is still active and if not, restores the fast path.
 161  * by construction a single eventfd is handled at a time.
 162  * if the IRQ is still active, the timer is re-programmed.
 163  */
 164 static void vfio_intp_mmap_enable(void *opaque)
 165 {
 166     VFIOINTp *tmp;
 167     VFIOPlatformDevice *vdev = (VFIOPlatformDevice *)opaque;
 168
 169     QEMU_LOCK_GUARD(&vdev->intp_mutex);
 170     QLIST_FOREACH(tmp, &vdev->intp_list, next) {
 171         if (tmp->state == VFIO_IRQ_ACTIVE) {
 172             trace_vfio_platform_intp_mmap_enable(tmp->pin);
 173             /* re-program the timer to check active status later */
 174             timer_mod(vdev->mmap_timer,
 175                       qemu_clock_get_ms(QEMU_CLOCK_VIRTUAL) +
 176                           vdev->mmap_timeout);
 177             return;
 178         }
 179     }
 180     vfio_mmap_set_enabled(vdev, true);
 181 }
 182
 183 /**
 184  * vfio_intp_inject_pending_lockheld - Injects a pending IRQ
 185  * @opaque: opaque pointer, in practice the VFIOINTp handle
 186  *
 187  * The function is called on a previous IRQ completion, from
 188  * vfio_platform_eoi, while the intp_mutex is locked.
 189  * Also in such situation, the slow path already is set and
 190  * the mmap timer was already programmed.
 191  */
 192 static void vfio_intp_inject_pending_lockheld(VFIOINTp *intp)
 193 {
 194     trace_vfio_platform_intp_inject_pending_lockheld(intp->pin,
 195                               event_notifier_get_fd(intp->interrupt));
 196
 197     intp->state = VFIO_IRQ_ACTIVE;
 198
 199     /* trigger the virtual IRQ */
 200     qemu_set_irq(intp->qemuirq, 1);
 201 }
 202
 203 /**
 204  * vfio_intp_interrupt - The user-side eventfd handler
 205  * @opaque: opaque pointer which in practice is the VFIOINTp handle
 206  *
 207  * the function is entered in event handler context:
 208  * the vIRQ is injected into the guest if there is no other active
 209  * or pending IRQ.
 210  */
 211 static void vfio_intp_interrupt(VFIOINTp *intp)
 212 {
 213     int ret;
 214     VFIOINTp *tmp;
 215     VFIOPlatformDevice *vdev = intp->vdev;
 216     bool delay_handling = false;
 217
 218     QEMU_LOCK_GUARD(&vdev->intp_mutex);
 219     if (intp->state == VFIO_IRQ_INACTIVE) {
 220         QLIST_FOREACH(tmp, &vdev->intp_list, next) {
 221             if (tmp->state == VFIO_IRQ_ACTIVE ||
 222                 tmp->state == VFIO_IRQ_PENDING) {
 223                 delay_handling = true;
 224                 break;
 225             }
 226         }
 227     }
 228     if (delay_handling) {
 229         /*
 230          * the new IRQ gets a pending status and is pushed in
 231          * the pending queue
 232          */
 233         intp->state = VFIO_IRQ_PENDING;
 234         trace_vfio_intp_interrupt_set_pending(intp->pin);
 235         QSIMPLEQ_INSERT_TAIL(&vdev->pending_intp_queue,
 236                              intp, pqnext);
 237         event_notifier_test_and_clear(intp->interrupt);
 238         return;
 239     }
 240
 241     trace_vfio_platform_intp_interrupt(intp->pin,
 242                               event_notifier_get_fd(intp->interrupt));
 243
 244     ret = event_notifier_test_and_clear(intp->interrupt);
 245     if (!ret) {
 246         error_report("Error when clearing fd=%d (ret = %d)",
 247                      event_notifier_get_fd(intp->interrupt), ret);
 248     }
 249
 250     intp->state = VFIO_IRQ_ACTIVE;
 251
 252     /* sets slow path */
 253     vfio_mmap_set_enabled(vdev, false);
 254
 255     /* trigger the virtual IRQ */
 256     qemu_set_irq(intp->qemuirq, 1);
 257
 258     /*
 259      * Schedule the mmap timer which will restore fastpath when no IRQ
 260      * is active anymore
 261      */
 262     if (vdev->mmap_timeout) {
 263         timer_mod(vdev->mmap_timer,
 264                   qemu_clock_get_ms(QEMU_CLOCK_VIRTUAL) +
 265                       vdev->mmap_timeout);
 266     }
 267 }
 268
 269 /**
 270  * vfio_platform_eoi - IRQ completion routine
 271  * @vbasedev: the VFIO device handle
 272  *
 273  * De-asserts the active virtual IRQ and unmasks the physical IRQ
 274  * (effective for level sensitive IRQ auto-masked by the  VFIO driver).
 275  * Then it handles next pending IRQ if any.
 276  * eoi function is called on the first access to any MMIO region
 277  * after an IRQ was triggered, trapped since slow path was set.
 278  * It is assumed this access corresponds to the IRQ status
 279  * register reset. With such a mechanism, a single IRQ can be
 280  * handled at a time since there is no way to know which IRQ
 281  * was completed by the guest (we would need additional details
 282  * about the IRQ status register mask).
 283  */
 284 static void vfio_platform_eoi(VFIODevice *vbasedev)
 285 {
 286     VFIOINTp *intp;
 287     VFIOPlatformDevice *vdev =
 288         container_of(vbasedev, VFIOPlatformDevice, vbasedev);
 289
 290     QEMU_LOCK_GUARD(&vdev->intp_mutex);
 291     QLIST_FOREACH(intp, &vdev->intp_list, next) {
 292         if (intp->state == VFIO_IRQ_ACTIVE) {
 293             trace_vfio_platform_eoi(intp->pin,
 294                                 event_notifier_get_fd(intp->interrupt));
 295             intp->state = VFIO_IRQ_INACTIVE;
 296
 297             /* deassert the virtual IRQ */
 298             qemu_set_irq(intp->qemuirq, 0);
 299
 300             if (vfio_irq_is_automasked(intp)) {
 301                 /* unmasks the physical level-sensitive IRQ */
 302                 vfio_unmask_single_irqindex(vbasedev, intp->pin);
 303             }
 304
 305             /* a single IRQ can be active at a time */
 306             break;
 307         }
 308     }
 309     /* in case there are pending IRQs, handle the first one */
 310     if (!QSIMPLEQ_EMPTY(&vdev->pending_intp_queue)) {
 311         intp = QSIMPLEQ_FIRST(&vdev->pending_intp_queue);
 312         vfio_intp_inject_pending_lockheld(intp);
 313         QSIMPLEQ_REMOVE_HEAD(&vdev->pending_intp_queue, pqnext);
 314     }
 315 }
 316
 317 /**
 318  * vfio_start_eventfd_injection - starts the virtual IRQ injection using
 319  * user-side handled eventfds
 320  * @sbdev: the sysbus device handle
 321  * @irq: the qemu irq handle
 322  */
 323
 324 static void vfio_start_eventfd_injection(SysBusDevice *sbdev, qemu_irq irq)
 325 {
 326     VFIOPlatformDevice *vdev = VFIO_PLATFORM_DEVICE(sbdev);
 327     VFIOINTp *intp;
 328
 329     QLIST_FOREACH(intp, &vdev->intp_list, next) {
 330         if (intp->qemuirq == irq) {
 331             break;
 332         }
 333     }
 334     assert(intp);
 335
 336     if (vfio_set_trigger_eventfd(intp, vfio_intp_interrupt)) {
 337         abort();
 338     }
 339 }
 340
 341 /*
 342  * Functions used for irqfd
 343  */
 344
 345 /**
 346  * vfio_set_resample_eventfd - sets the resamplefd for an IRQ
 347  * @intp: the IRQ struct handle
 348  * programs the VFIO driver to unmask this IRQ when the
 349  * intp->unmask eventfd is triggered
 350  */
 351 static int vfio_set_resample_eventfd(VFIOINTp *intp)
 352 {
 353     int32_t fd = event_notifier_get_fd(intp->unmask);
 354     VFIODevice *vbasedev = &intp->vdev->vbasedev;
 355     Error *err = NULL;
 356     int ret;
 357
 358     qemu_set_fd_handler(fd, NULL, NULL, NULL);
 359     ret = vfio_set_irq_signaling(vbasedev, intp->pin, 0,
 360                                  VFIO_IRQ_SET_ACTION_UNMASK, fd, &err);
 361     if (ret) {
 362         error_reportf_err(err, VFIO_MSG_PREFIX, vbasedev->name);
 363     }
 364     return ret;
 365 }
 366
 367 /**
 368  * vfio_start_irqfd_injection - starts the virtual IRQ injection using
 369  * irqfd
 370  *
 371  * @sbdev: the sysbus device handle
 372  * @irq: the qemu irq handle
 373  *
 374  * In case the irqfd setup fails, we fallback to userspace handled eventfd
 375  */
 376 static void vfio_start_irqfd_injection(SysBusDevice *sbdev, qemu_irq irq)
 377 {
 378     VFIOPlatformDevice *vdev = VFIO_PLATFORM_DEVICE(sbdev);
 379     VFIOINTp *intp;
 380
 381     if (!kvm_irqfds_enabled() || !kvm_resamplefds_enabled() ||
 382         !vdev->irqfd_allowed) {
 383         goto fail_irqfd;
 384     }
 385
 386     QLIST_FOREACH(intp, &vdev->intp_list, next) {
 387         if (intp->qemuirq == irq) {
 388             break;
 389         }
 390     }
 391     assert(intp);
 392
 393     if (kvm_irqchip_add_irqfd_notifier(kvm_state, intp->interrupt,
 394                                    intp->unmask, irq) < 0) {
 395         goto fail_irqfd;
 396     }
 397
 398     if (vfio_set_trigger_eventfd(intp, NULL) < 0) {
 399         goto fail_vfio;
 400     }
 401     if (vfio_irq_is_automasked(intp)) {
 402         if (vfio_set_resample_eventfd(intp) < 0) {
 403             goto fail_vfio;
 404         }
 405         trace_vfio_platform_start_level_irqfd_injection(intp->pin,
 406                                     event_notifier_get_fd(intp->interrupt),
 407                                     event_notifier_get_fd(intp->unmask));
 408     } else {
 409         trace_vfio_platform_start_edge_irqfd_injection(intp->pin,
 410                                     event_notifier_get_fd(intp->interrupt));
 411     }
 412
 413     intp->kvm_accel = true;
 414
 415     return;
 416 fail_vfio:
 417     kvm_irqchip_remove_irqfd_notifier(kvm_state, intp->interrupt, irq);
 418     abort();
 419 fail_irqfd:
 420     vfio_start_eventfd_injection(sbdev, irq);
 421     return;
 422 }
 423
 424 /* VFIO skeleton */
 425
 426 static void vfio_platform_compute_needs_reset(VFIODevice *vbasedev)
 427 {
 428     vbasedev->needs_reset = true;
 429 }
 430
 431 /* not implemented yet */
 432 static int vfio_platform_hot_reset_multi(VFIODevice *vbasedev)
 433 {
 434     return -1;
 435 }
 436
 437 /**
 438  * vfio_populate_device - Allocate and populate MMIO region
 439  * and IRQ structs according to driver returned information
 440  * @vbasedev: the VFIO device handle
 441  * @errp: error object
 442  *
 443  */
 444 static int vfio_populate_device(VFIODevice *vbasedev, Error **errp)
 445 {
 446     VFIOINTp *intp, *tmp;
 447     int i, ret = -1;
 448     VFIOPlatformDevice *vdev =
 449         container_of(vbasedev, VFIOPlatformDevice, vbasedev);
 450
 451     if (!(vbasedev->flags & VFIO_DEVICE_FLAGS_PLATFORM)) {
 452         error_setg(errp, "this isn't a platform device");
 453         return ret;
 454     }
 455
 456     vdev->regions = g_new0(VFIORegion *, vbasedev->num_regions);
 457
 458     for (i = 0; i < vbasedev->num_regions; i++) {
 459         char *name = g_strdup_printf("VFIO %s region %d\n", vbasedev->name, i);
 460
 461         vdev->regions[i] = g_new0(VFIORegion, 1);
 462         ret = vfio_region_setup(OBJECT(vdev), vbasedev,
 463                                 vdev->regions[i], i, name);
 464         g_free(name);
 465         if (ret) {
 466             error_setg_errno(errp, -ret, "failed to get region %d info", i);
 467             goto reg_error;
 468         }
 469     }
 470
 471     vdev->mmap_timer = timer_new_ms(QEMU_CLOCK_VIRTUAL,
 472                                     vfio_intp_mmap_enable, vdev);
 473
 474     QSIMPLEQ_INIT(&vdev->pending_intp_queue);
 475
 476     for (i = 0; i < vbasedev->num_irqs; i++) {
 477         struct vfio_irq_info irq = { .argsz = sizeof(irq) };
 478
 479         irq.index = i;
 480         ret = ioctl(vbasedev->fd, VFIO_DEVICE_GET_IRQ_INFO, &irq);
 481         if (ret) {
 482             error_setg_errno(errp, -ret, "failed to get device irq info");
 483             goto irq_err;
 484         } else {
 485             trace_vfio_platform_populate_interrupts(irq.index,
 486                                                     irq.count,
 487                                                     irq.flags);
 488             intp = vfio_init_intp(vbasedev, irq, errp);
 489             if (!intp) {
 490                 ret = -1;
 491                 goto irq_err;
 492             }
 493         }
 494     }
 495     return 0;
 496 irq_err:
 497     timer_del(vdev->mmap_timer);
 498     QLIST_FOREACH_SAFE(intp, &vdev->intp_list, next, tmp) {
 499         QLIST_REMOVE(intp, next);
 500         g_free(intp);
 501     }
 502 reg_error:
 503     for (i = 0; i < vbasedev->num_regions; i++) {
 504         if (vdev->regions[i]) {
 505             vfio_region_finalize(vdev->regions[i]);
 506         }
 507         g_free(vdev->regions[i]);
 508     }
 509     g_free(vdev->regions);
 510     return ret;
 511 }
 512
 513 /* specialized functions for VFIO Platform devices */
 514 static VFIODeviceOps vfio_platform_ops = {
 515     .vfio_compute_needs_reset = vfio_platform_compute_needs_reset,
 516     .vfio_hot_reset_multi = vfio_platform_hot_reset_multi,
 517     .vfio_eoi = vfio_platform_eoi,
 518 };
 519
 520 /**
 521  * vfio_base_device_init - perform preliminary VFIO setup
 522  * @vbasedev: the VFIO device handle
 523  * @errp: error object
 524  *
 525  * Implement the VFIO command sequence that allows to discover
 526  * assigned device resources: group extraction, device
 527  * fd retrieval, resource query.
 528  * Precondition: the device name must be initialized
 529  */
 530 static int vfio_base_device_init(VFIODevice *vbasedev, Error **errp)
 531 {
 532     VFIOGroup *group;
 533     VFIODevice *vbasedev_iter;
 534     char *tmp, group_path[PATH_MAX], *group_name;
 535     ssize_t len;
 536     struct stat st;
 537     int groupid;
 538     int ret;
 539
 540     /* @sysfsdev takes precedence over @host */
 541     if (vbasedev->sysfsdev) {
 542         g_free(vbasedev->name);
 543         vbasedev->name = g_path_get_basename(vbasedev->sysfsdev);
 544     } else {
 545         if (!vbasedev->name || strchr(vbasedev->name, '/')) {
 546             error_setg(errp, "wrong host device name");
 547             return -EINVAL;
 548         }
 549
 550         vbasedev->sysfsdev = g_strdup_printf("/sys/bus/platform/devices/%s",
 551                                              vbasedev->name);
 552     }
 553
 554     if (stat(vbasedev->sysfsdev, &st) < 0) {
 555         error_setg_errno(errp, errno,
 556                          "failed to get the sysfs host device file status");
 557         return -errno;
 558     }
 559
 560     tmp = g_strdup_printf("%s/iommu_group", vbasedev->sysfsdev);
 561     len = readlink(tmp, group_path, sizeof(group_path));
 562     g_free(tmp);
 563
 564     if (len < 0 || len >= sizeof(group_path)) {
 565         ret = len < 0 ? -errno : -ENAMETOOLONG;
 566         error_setg_errno(errp, -ret, "no iommu_group found");
 567         return ret;
 568     }
 569
 570     group_path[len] = 0;
 571
 572     group_name = basename(group_path);
 573     if (sscanf(group_name, "%d", &groupid) != 1) {
 574         error_setg_errno(errp, errno, "failed to read %s", group_path);
 575         return -errno;
 576     }
 577
 578     trace_vfio_platform_base_device_init(vbasedev->name, groupid);
 579
 580     group = vfio_get_group(groupid, &address_space_memory, errp);
 581     if (!group) {
 582         return -ENOENT;
 583     }
 584
 585     QLIST_FOREACH(vbasedev_iter, &group->device_list, next) {
 586         if (strcmp(vbasedev_iter->name, vbasedev->name) == 0) {
 587             error_setg(errp, "device is already attached");
 588             vfio_put_group(group);
 589             return -EBUSY;
 590         }
 591     }
 592     ret = vfio_get_device(group, vbasedev->name, vbasedev, errp);
 593     if (ret) {
 594         vfio_put_group(group);
 595         return ret;
 596     }
 597
 598     ret = vfio_populate_device(vbasedev, errp);
 599     if (ret) {
 600         vfio_put_group(group);
 601     }
 602
 603     return ret;
 604 }
 605
 606 /**
 607  * vfio_platform_realize  - the device realize function
 608  * @dev: device state pointer
 609  * @errp: error
 610  *
 611  * initialize the device, its memory regions and IRQ structures
 612  * IRQ are started separately
 613  */
 614 static void vfio_platform_realize(DeviceState *dev, Error **errp)
 615 {
 616     VFIOPlatformDevice *vdev = VFIO_PLATFORM_DEVICE(dev);
 617     SysBusDevice *sbdev = SYS_BUS_DEVICE(dev);
 618     VFIODevice *vbasedev = &vdev->vbasedev;
 619     int i, ret;
 620
 621     vbasedev->type = VFIO_DEVICE_TYPE_PLATFORM;
 622     vbasedev->dev = dev;
 623     vbasedev->ops = &vfio_platform_ops;
 624
 625     qemu_mutex_init(&vdev->intp_mutex);
 626
 627     trace_vfio_platform_realize(vbasedev->sysfsdev ?
 628                                 vbasedev->sysfsdev : vbasedev->name,
 629                                 vdev->compat);
 630
 631     ret = vfio_base_device_init(vbasedev, errp);
 632     if (ret) {
 633         goto out;
 634     }
 635
 636     if (!vdev->compat) {
 637         GError *gerr = NULL;
 638         gchar *contents;
 639         gsize length;
 640         char *path;
 641
 642         path = g_strdup_printf("%s/of_node/compatible", vbasedev->sysfsdev);
 643         if (!g_file_get_contents(path, &contents, &length, &gerr)) {
 644             error_setg(errp, "%s", gerr->message);
 645             g_error_free(gerr);
 646             g_free(path);
 647             return;
 648         }
 649         g_free(path);
 650         vdev->compat = contents;
 651         for (vdev->num_compat = 0; length; vdev->num_compat++) {
 652             size_t skip = strlen(contents) + 1;
 653             contents += skip;
 654             length -= skip;
 655         }
 656     }
 657
 658     for (i = 0; i < vbasedev->num_regions; i++) {
 659         if (vfio_region_mmap(vdev->regions[i])) {
 660             warn_report("%s mmap unsupported, performance may be slow",
 661                         memory_region_name(vdev->regions[i]->mem));
 662         }
 663         sysbus_init_mmio(sbdev, vdev->regions[i]->mem);
 664     }
 665 out:
 666     if (!ret) {
 667         return;
 668     }
 669
 670     if (vdev->vbasedev.name) {
 671         error_prepend(errp, VFIO_MSG_PREFIX, vdev->vbasedev.name);
 672     } else {
 673         error_prepend(errp, "vfio error: ");
 674     }
 675 }
 676
 677 static const VMStateDescription vfio_platform_vmstate = {
 678     .name = "vfio-platform",
 679     .unmigratable = 1,
 680 };
 681
 682 static Property vfio_platform_dev_properties[] = {
 683     DEFINE_PROP_STRING("host", VFIOPlatformDevice, vbasedev.name),
 684     DEFINE_PROP_STRING("sysfsdev", VFIOPlatformDevice, vbasedev.sysfsdev),
 685     DEFINE_PROP_BOOL("x-no-mmap", VFIOPlatformDevice, vbasedev.no_mmap, false),
 686     DEFINE_PROP_UINT32("mmap-timeout-ms", VFIOPlatformDevice,
 687                        mmap_timeout, 1100),
 688     DEFINE_PROP_BOOL("x-irqfd", VFIOPlatformDevice, irqfd_allowed, true),
 689     DEFINE_PROP_END_OF_LIST(),
 690 };
 691
 692 static void vfio_platform_class_init(ObjectClass *klass, void *data)
 693 {
 694     DeviceClass *dc = DEVICE_CLASS(klass);
 695     SysBusDeviceClass *sbc = SYS_BUS_DEVICE_CLASS(klass);
 696
 697     dc->realize = vfio_platform_realize;
 698     device_class_set_props(dc, vfio_platform_dev_properties);
 699     dc->vmsd = &vfio_platform_vmstate;
 700     dc->desc = "VFIO-based platform device assignment";
 701     sbc->connect_irq_notifier = vfio_start_irqfd_injection;
 702     set_bit(DEVICE_CATEGORY_MISC, dc->categories);
 703     /* Supported by TYPE_VIRT_MACHINE */
 704     dc->user_creatable = true;
 705 }
 706
 707 static const TypeInfo vfio_platform_dev_info = {
 708     .name = TYPE_VFIO_PLATFORM,
 709     .parent = TYPE_SYS_BUS_DEVICE,
 710     .instance_size = sizeof(VFIOPlatformDevice),
 711     .class_init = vfio_platform_class_init,
 712     .class_size = sizeof(VFIOPlatformDeviceClass),
 713 };
 714
 715 static void register_vfio_platform_dev_type(void)
 716 {
 717     type_register_static(&vfio_platform_dev_info);
 718 }
 719
 720 type_init(register_vfio_platform_dev_type)